Topband: Beverage Feed Line Choke Installation

Herbert Schoenbohm herbs at vitelcom.net
Tue Jun 2 06:23:47 PDT 2009


Has anyone tried 75 ohm triax video cable with the outside shield floating 
at one end and earth at the other in the form of a Faraday sheild in feeding 
a Beverage matching network?  Or even shielded 75 ohm twisted pair with a 
simple balun at each end with the normal Beverage ground in place.

The Faraday shield used to work for me for long video and audio runs to get 
rid of hum.  Yes I know the hum was VLF and related to 60hz mains common 
mode pickup....but would the prinicple of a Faraday work at 1.8 especially 
if multiples of a quarter wave were used to get out to the feed point.

The reason I ask is that the original Beverage designs included Faraday 
shields on the matching networks but no mention is made today as that 
possible solution to random pickup.

Herb, KV4FZ 



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